<p>I have heard that at some schools, you will go through a round of interviews of 3 or 4 PI's that you have chosen. After the interview, you will rank the PI's based on preference, and the PI's likewise will rank the students. The PI with whom you have the best match is usually going to be your advisor.</p>
<p>Now, I used to think that you would have complete freedom regarding your choice of PI, but as mentioned above, that seems not to be the case. For those looking to go into academia, the PI is extremely important. Some PI's, no matter how well known they are, will not place any of their grads into academia, while others may place up to 70%. </p>
<p>So the question is, just how much freedom do you have in choosing your PI? Is it simply just narrowing them down to a list of 3-4 and then after that, somewhat out of your control? Also, suppose you have identified exactly one PI in the department that you want to work for, and that is the sole reason why you are applying to that particular grad school. Are you guaranteed placement with that PI if accepted? I ask because I feel I may already have decided what sub-sub niche in academic research I want to explore in grad school, and may only seek out specific PI's and not necessarily specific departments. Because I think if the applicant is dead-set on a sub-sub field, then it is the PI level that will make a difference, whereas if he/she is just looking into the general area, then the department level is sufficient resolution.</p>